The present invention relates to a locking device for lock components in or on vehicles, of the type having at least two closure elements located in spaced separation from one another and coupled to a control operating mechanism such as a lock cylinder. Locking devices of this general type are known to the art, as illustrated for example by German Offenlegungsschrift 3,642,242, which discloses a locking device adapted for two-point locking of doors, hoods or tailgates of vehicles, utilizing rotary-latch closures of the fork type conventional on vehicle doors. With the lock component opened, the rotary latch closures are held in their release position under a spring load. When the lock component is shut, the latch closures are rotated into their locking position by running with one fork end onto the associated catch bolt of the counter-component. In their locking position, the latch closures are blocked against pivoting by means of an automatic detent mechanism, so that the catch bolts, surrounded by their rotary-latch fork, are held in their closing position
However, when the lock component is shut, the desired two-point locking is obtained only when the catch bolts strike virtually simultaneously against the corresponding forked rotary latches. If one of the catch bolts has too great a lead in relation to the other catch bolt, the catch bolt which first strikes its associated closure unit is rotated into its locking position without the associated forked rotary latch being capable of surrounding the second catch bolt as well. As a result, although both forked rotary latches are in their locking position, there is only a one-point locking of the lock component. The security of the lock component with single-point locking is even lower than in conventional lock components having only one locking point, but arranged centrally.
The known locking device is therefore suitable only for extremely torsion-resistant lock components which interact with a likewise torsion-resistant counter-component.
Furthermore, it is also known to use individual rotary closures on commercial ski carriers, wherein pivotably fastened shackles of the ski carrier can be locked only when they have also reached their closing position. As a control member there is a detent lever, by means of which the rotary closure designed as a closure hook is blocked against pivoting into its release position. The detent lever articulated on the closure housing is held in its blocking position by means of a tension spring connecting it to the closure hook. At the same time, a longitudinal portion of the detent lever projects into an end region of a latch orifice of the closure housing so that it is pivoted by the penetration of the catch bolt into the latch orifice. When the end position of the catch bolt in the latch orifice is reached, the detent lever is pivoted to such an extent that the rotary closure is released to advance into its locked position. At this moment, the prestressed tension spring automatically draws the rotary closure into its locking position. A core of a lock cylinder corotated by the rotary closure snapping shut is thereby transferred into its key withdrawal position, after which the one-point locking of the shackle can be secured simply by withdrawing the key.
One object of the present invention is to provide a locking device of the generic type described above, having the additional feature that during the locking of the closure unit by the associated catch bolts, a two-point locking of the lock component can be ensured largely independently of the torsional stability of the lock component or of the counter-component.
This object is achieved in a locking device according to the present invention by providing a separate sequence control for each of the two rotary closures of the closure unit. If, during the closing of the lock component, one of the two catch bolts has not reached its lockable end position, each of the rotary closure elements remains blocked in its release position. Although the other rotary closure is no longer blocked by its associated control member, it is held in the release position as a result of its rotational coupling to the other, still blocked, rotary closure. One-point locking of the locking device is thus prevented completely.
In an especially simple embodiment of the invention, each control member consists of a detent lever which is mounted pivotably on a closure housing and which interacts directly in a manner that is known per se with a rotary closure designed as a closure hook. However, because of their spring loading in the locking direction, such snap closures cannot be unlocked simply by tripping, but require a separate rotary drive, such as key operation of a lock cylinder, the cylinder core being rotationally coupled to the closure unit. Moreover, the locking position of the closure unit can be secured additionally via the lock cylinder when there is an appropriate key withdrawal position.
A restriction to a single key withdrawal position available in the locking position of the closure unit simplifies the operation of the locking device, since, with the key withdrawn, a locking of the lock component is always assured.
If a rotary closure is located with its end face opposite an accessible housing shell of the lock component at not too great a distance, the lock cylinder can be set into the wall surface and, being arranged coaxially relative to the axis of rotation of the rotary closure, can be rotationally coupled directly thereto. To allow a completely countersunk installed position of the lock cylinder despite the location of the rotary closure near the housing shell, the cylinder core can be connected to the rotary closure at the head end equipped with the key insertion orifice, all space-saving types of driving connections being possible for the rotational connection.
The advantage of this design is that the necessary length of the transmission element between the rotary closures can be reduced by the length of the cylinder housing. If the transmission element consists of a torsion-resistant hollow shaft or the like, such a reduction of the length of the transmission element can lead to an appreciable weight saving.
The locking device according to the present invention has proved especially advantageous in conjunction with a lightweight tubular frame as a lock component. It is particularly suitable as a locking device for a tilting frame of a load carrier which, for example, may be attached to a trunk lid of a motor vehicle. Tilting frames of this type make it possible to open the trunk lid when the tilting frame is swung up whilst, with the boot lid closed, the tilting frame, in its closing position, must be locked securely with a basic frame of the load carrier.
If the two individual closures of the tilting frame which are known, for example, from German Utility Model 8616177.6 are replaced by the locking device, the tilting frame can be operating from a side of the vehicle. Since trunk-loading activities often have to take place in a traffic flow, the gain in safety achieved by means of the locking device is considerable.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.